1. Field of the Invention
The present invention relates to a steering wheel core for a vehicle and, more particularly, to a steering wheel core including a ring and a boss connected to each other by spokes which are constructed to absorb an impact applied thereto.
2. Description of Related Art
A conventional steering wheel having a core is disclosed in U.S. Pat. No. 5,085,097. As shown in FIG. 9, a core 31 includes a ring 32, a boss 33 about which the steering wheel is rotated, and spokes 34 connecting the ring 32 and the boss 33. The ring 32 and the spokes 34 are made of materials having sufficient strengths and rigidities. The core 31 so constructed ensures a strong and rigid steering wheel. In ordinary use, therefore, the steering wheel does not deform due to stresses applied thereto.
As noted above, the conventional core 31, including the ring 32 and the spoke 34 is rigid. However, due to this high rigidity, problems may arise. More specifically, in the conventional steering wheel, the spokes 34 have the greatest rigidity. If an impact is applied to the steering wheel in the direction indicated by arrow A in FIG. 9, the spokes 34 will not readily deform. As a result, the aforementioned impact may not be absorbed sufficiently.
In order to resolve the above-specified problems, it is conceivable to reduce the rigidity and strength of the spokes 34. In this case, however, the performance characteristics of the steering wheel itself, in ordinary use, such as the vibration characteristics or operation characteristics, will decline. As a result, the core may fail to exhibit its functions sufficiently if the rigidity and strength of the spokes 34 are reduced.